Performance and combustion study of a low heat rejection engine running with biogas–diethyl ether–diesel

The present research focuses on addressing the faster depletion of fossil fuels and environmental pollution in addition to the energy crisis that hinders the progress of a nation. In the current research, waste banana leaves were considered as substrates for biogas production. Biogas is taken as the primary fuel in dual fuel (DF) operations to maximize possible diesel savings. The performance and combustion assessment were executed in a low heat rejection (LHR) engine using 5% diethyl ether by volume blended with diesel (5DEE) as pilot fuel. The combustion attributes of the engine reveal that the apex of net heat release rate (NHRR) curve retarded a bit as compared to apex of base result. The peak cylinder pressure was noted to be 6.19 MPa in the LHR engine running with 5DEE + biogas at 11.7° crank angle (CA) after top dead center (aTDC) compared to 5.23 MPa for the diesel alone operation at the same position. The apex point for NHRR was observed to be 54.51 J (°)⁻¹ for 5DEE + biogas in LHR engine positioned at 3.2° aTDC. The brake thermal efficiency at full engine load operation decreased by 12.7% and 5.2% for biogas substitutions of 0.8 kg h⁻¹ with diesel and 5DEE, respectively, compared to the base result. The smoke opacity and nitric oxide emissions were reduced during the DF run accompanied by diethyl ether as a fuel additive.

Graphical abstract